Internal-combustion engine



May 8, 1923.

A. L. POWELL INTERNAL COMBUSTION 'ENGINE Filed Dec. 24, 1920 zlwuentz I A VAHL. rownrncoruivririns:any, nonre'nanssrenonro'rntn A. LJroWE nrowER specification.

i 4 0., 0]? MILES CITY, MONTANA, AIQORPORATIOYN.

,mT EnN'A -coMBUsr-ronfErmine.

' Application filed Decemberfl, 1920. Serial noj 'yiaaoaai v To all whom it may concern: I

Be it knownrthatI, ALVAI-I L. 199m a citizen of the United' States, residing at Miles City, in the county of Custer andState of Montana, have invented certain new'and" useful Improvements" in Internal-Combustion Engines, of, which the following 1s a My inventionrelates to improvements in internal combustion engines in which'I provide for concentrating the piston power at an advantageous partof the crank circle, for distributing the piston pressure more uniformly, andfor increasing thefthermal eili ciency as a whole by absorbing an amount of heat which would otherwise be lost.

In the accompanying drawings F1g. 1. 1s

a vertical elevation in section, showing an application of my improvement to a two cycle engine. v

Fig. 2 is aplan of the piston, showing the arrangement of battle plates to absorb heat.

I Fig. 3 is a diagram ofthe operation .of an engine of the four cycle type.

I by thecapB and bolts B I also show inlet .In Fig. 1 a piston A in a cylinder A is slidably fitted in the latter. The piston A 1s counterbored and a second piston, Aflfitted- .to it in slidable relation. In piston A219 a wrist pin, A on which swings a piston rod, .21 In the lower section of A a'ring is threaded in, A to serve as a retaining means for piston A On lower end of A there is a minor piston, A, in which are small air holes, as shown. A fitsin. a cylindrical space in a member Aflthat is pivoted on wrist pin A on' engine crank A ,;and1secured thereto and exhaust ports at B B3, to which proper valves can be attached for a two cycle en- ,gine. w

' In the position shown in Fig. 1 the main piston is at" top stroke. On outstroke ignition occurs andforce is applied to-piston A As A is loose on piston A the first effect of this'is to reduce the space between said pistons, at X, thepressure in'this spacerising until it equals that of the explosion. Both pistons, then move on together. Itwill'be seen, by examining drawing, that A will be bearing on the bottom of the cylindrical passage in vwhich it slides, and the pressure will cause the crank A to begin rotation. As A 7 moves out the pressure in the combustion p'ansionuof ithe" air 'in' Xland a" retarding chamber will falh but this willilea'd: to efx T 55,, 7 effect on A? will take place.;' This will be;

balanced by the equalization of pressure, the pressure incombus'tion chamber and Xrauto-r maticallyadjusting themselves. thejearly part of movement of A thewrist I'p'in' I1 Wil1-be passing through a part of the'cra'nk circle where the angul'arity"Iof motion with reference tocenter line of engine will not be,

favorable to high mechanicalleificiencyf-but as, it adva'nces the effectiveness ofthrust in r creases, and the additional push imparted by the expansion in X acts under conditions". 3

conversivej to I high efficiency. The """compressed air in the spacedk ii's further in? .70 from pisto'nfand cylinder walls, and this.

creased in pressure by adsorption'of heat added energy isgivenup, to the crank."TheI*' chamber X'is assumed to have an original charge-of air atatmospheric pressure, introduced at the time oft-assembling" the engine; On reaching the point a (Fig. 1) the crank continues to advance, but the pistons remain stationary; The ports indicated a-tj'B ,,B are uncovered as the piston A? reaches theposition described, and exhaust ,takes' place.

through B When pressure has fallen to.

a point equaling, orlo'werthan the air pres-1 I sure in crank case'i(not shown),- air 1 enters the-cylinder, with a properproportion of it Onthe crank circle, Fig.1, the opening ofex'haustcg and its closing at .ici p This Ilsecure by'a difference i'npstroke of; .1

fuel from an convenient source.

is indicated at a piston A in reference. tocrank stroke, the

moves piston A by1reason, of the'gair com pressed between them. I causesmall relief;

holes to' be drilled through piston A by whichfthe"compression may relieve itse'lfi' this also serving as a cushion to preventnoist or shock. t

In Fig.2 th'ejbafiie plateor sectionson 1 I latter 'being".greaterthanz'the former. On}? reaching a. the effect of thisldifi'erence. begf comes anoperative factor,'.the crankdraw-f I ing away from theminor'" piston 'A 'which: 1

then hasa position in theupper part of the, cylindrical passage in which it"moves, ;Tliis action continues'from a to c,-where a reverse I efi'ect begins. Pressure develops'underjpis f i i y ton A, the airbeneathyitjbeing-'compressedg f and'it reacts onpistonA -which,"inflturn. I160.

' are shown. This increases the surface, the

heat being more quickly taken up by th compressed air in X.

In Fig. 3 the diagram shows the operation in case of a four cycle engine.

In this way I obtain a structure relatively simple and of 'high'mechanical and thermal efficiency. 1

What I believe is new and ask to have protected by Letters l atent, is

1. In an internal combustion engine, the combination of a power cylinder, a primary piston located therein and a secondary piston, the said secondary piston slidable in the said primary piston, an airspace between said pistons, heat absorption surfaces in the said primary piston for absorbing heat from the explosive gases in the power cylinder; a piston rod, a crank, a power shaft; connecting means between said secondary piston and said piston rod, crank and power shaft, whereby the force exerted against the said primary piston is transmitted to the sait crank in the form of power and to the air space in the form of heat, the movement of the crank being maintained thereby at the points of its stroke most favorable to power reception, by the expansion of the air between said pistons, substantially as described. I

" 2. In an internal combustion engine, a power cylinder, a primary pistonslid'able in said cylinder, a secondarypiston slidable in said primary piston, an air space between said pistons, heat absorbing surfaces in said air space, a piston rod, a minor piston on,

said piston rod, means for connecting said piston rod to said secondary piston; a power crank, a power shaft, a cyllndrical chamber forming part of said power crank, means for moving; said power crank by said piston rod and said minor piston, means for alternately compressing and discharging air from said cylindrical chamber by the action of the said minor piston, means for rotating said power crank by the force developediin the said power cylinder, andmeans for maintaining the movement of said power crank while it is traveling through that part of crank circle of greatest mechanical effect, by the expansion of the air in said air space betyeen said primary and secondary pistons, substantially as described. c

In testimony whereof I afiix my signature.

ALVAH rowE L. 

